Prevention of coil slippage on mandrels



- h rfi went, h his sten Wire, is wounds-0n Patented July 28, 1925.

EDWARD ROBERT or moms, nnw'rrmsny, ASSIG'N-OR T0 Lmrconm, n ponronmuox or BENNSYLVANIA. I

' Iranian-rm: or com summer: on "Mmnmans.

' in, Drawin lh ncmua eaa isr1a,libzagIs fii no. 658,185.; I I (r a m-hm t vn m i w t known ,th,at VI, Em

v v I V I AlmigRonnnr length ofeach Isecti'on depending on the size min), a .citizenofthe United.States, and a resident of Verona, in the county ofEssex and, stateofgNew Jersey, have invented a new andnsefnl Improvement in the Prevention of Coil SIi Page'pnMand-reb, of which the gfol-lowing. is. a specification. W I

This invention rgalatestothewinding of coils of tungsten 'Wire or the like on mandrels and more particularly :tothe prevention ofsIi age fsnGh on the mandrels, after they are cut. to length for use ineandescible filamentsin electric lamps orfthe like.

cult has been experienced from slippage .of t e tungsten coil drel hile .the'isame is being cutin-t'o sections of the desired length; This-istundesirable in that it affects the accuracy Withvhic-hthe coiledfilament out into sections. II 'Vnr'idus expedients have been devised for eliminating this trouble, for examplefif the annealed at ,anrelatively high temperature, so that substantially all resiliency istretionof a [solution to wire, often-the s me is wound on amendrel, to :act esan adhesive and p wi' eflk t e w u d e t i s -m jandre'l, so that wire, and mandrelmay hi f-mfinve tiq th app e fl fi imaildrl' fi me is g y ox d zed, there is not great danger of slippagethereon, However, it is desirableto perform the annealing operation-at .a relaboth be cut tolengtl f without slippage there- .9 obv t ngs ipp ge is i c osed in the c bdtween ,v 'i, I A1 h r.; l o my; i e on ist employment of an inorganio salt which is r-r ad y ble n he ie p y .i v.

, 1y lo ei c dw enior z pp e. t m as w fim uee L m pa a J at .hot solution to, coiled; filament on a man-N .Smd apphcatronkd scloses the ,rougl ening fi men-the Maw-event ng iv ifl dr e t ms 'hes e nt ttheggbgtween while cutting the (3011941 01 wound thereon pass ng the same through a bath material and then through an annealingiur- -n ace. resultsfiih arougliening roj lthe which consequently '.seri;a.1 No. e 52, L87, filed .July 19,1923, Methodiandlapparatus for preventing slippage ..fi m t nd e i irel i l -A iw bh r 12 3 o my invention isM-th .jww en em teoi edene m nd e 4 f o S nshereo y e lrt esq yi wee- I .I I qemi cifimathe w athota s l ien. o i seds @r Ye -t hpre pt h elled filo. igsodi um -tetnaborate orjitscquivalent, p menttthereon,

@A still further-ohjeet of my. invention is t iliza n o .a't i-n fil :Qf; b r i equivalent, to cause filamentary material, owhich es bw -w e n -eu i lifl Hsirahle and %oIod r-esu1ts have been obtained Jby- ;m rf 0 .made for providing a substance; with l nite sadhesive I properties for lholdingltlie fila- I n; e. rm-m lfwure of i de eib e fil men i o .gw dalam S M 11 lye f e 9 t m e w thwtsl p- Page en whil and t e putting into finished; II L I. v I" I: Qther objeotsandodvantages of the inermt n wi l .c .7 wool en file afi elm iwt fl-e fi ements i0 7 e w l d d d amps, t su e l we p p he-s me nit wio m f; hehcal, by w d g Mo n w nem d d, iir r ly o ronys o th m -L nw g in r n, A

preferably tungthe .modve en between the filament gamd roughened .1nandrel being relied ior this purpose. I

According to my invention, Iiprovide a tightly-adhesive film of 1nateria l, wh*-ieh is preferably applied to the I duel immediately after the annealing operat ion, rvhieh serves tolholdthe filament in place thereon eint'il the cutting operation has been com gfletednnd which makes it possible tofore,

Ilg =0r off the ma movedifrom the rv vou nd filament, especially:

tively low teinperature {and another means;

. of coil wound mandrel, 7 and, assigned to the;

of nitric acid or. equivalent;

The processdisclosed is de -q coil on the to .anneal at ,a lower temperature; than here t-s There are numenous ,Inaterials I whichoould ,be .used to form sneha binding wrismironoosn I annealed in plaee, it is cutdnto sections, the

. rrhehm for which his :to be used. cDi flimandrel with the filament wound thereon is i pending application of 'Schul and Hunt,

vvever, there is no provision ,rnent in place onthe mandrel he f ictiondw c film, but ,a I large fnurnberwof theni offer cu lties, in tha'tnthey can onlyybe; removed with the expenditure of considerable timer tungsten' filament, "the "borax film to the coiledfilament on the mandrehihe solving operation.

Undoubtedly, the same results might'be "obtained from other inorganic compounds,

for example, has afhi lr solubility in hot water comparatively low one in cold water. Such V amaterial should also form a flexible film 60 which does not react with tungsten, which does not undergo changes-when exposed to r the atmosphere and'whichcan' be dissolved and effort, involvev an extra operation and coiled filament on the mandrel, after the same has been annealed.

As the coiled filament and mandrel cools, the supersaturat'ion'point of the solution will be reached and a firmly adherent coating will remain to hold the coil in place on'the' mandrel.

" The same may then be wound up, out to the 'desiredlength or lengths, the mandrel re- 'move'd'and the coils treatedin'the usual manner I 1 My invention will, be better understood by aspecific description of a preferred embodiment thereofas follows, but it is to be understood that other materials than that 'mentioned'may be used Without departing from the spirit of my invention. Sodium tetraborate' or borax,

lOH 'Ofhasa high solubility in hot'water and is only slightly soluble in cold water. "'A' 50%' hot solution or boraX is therefore preferably preparedandcoils of filament wound on a mandrel, passed" through such t solution immediately after they have been passedfthrough the annealer. As the wire "cools, the'supersaturation point of the borax *film} is reached, resulting in the deposit of 5 a firmly-adherent coating of boraX thereon,

to hold the 'coil in place. on the mandrel. This-Thorax film is glass-like, relativelyflexible and exerts-no deleterious effect'on a :Atter' the application of same may be wound up on a spool as usual and when desired, it ma for example, by chloric or sulphuric acid solutions."

" the mandrel therefrom, may

I usual manner. "The vfilm of borax' thereon comes off readily during the mandrel 'dispotassium tetraborate which and a in hydrochloric or sulphuric acid solutions. Although I have described in detail, a

preferred method of practicing my invenadhesive material thereto.

2. The method of preventing filament coiled on a mandrel from slipping thereon comprising applying-a solution" of an "inorganic adhesive material thereto; a

' filament 3. Themethod of preventing coiled-011a mandrel'from slipping thereon 4. The method" of preventing filalilent coiled on a Ymandrelfrom slipping thereon comprising applyinga "hot solution of an alkali bo'rate thereto. 1

'5; The method of preventing a metal filament coiled on a 'mandrelffrom slipping thereon, comprising applying a hot supersaturated solution of an alkali b'orate' thereto, whereby a film'otadhesive material sets thereon "immediately" upon cooling.

f' GJThe' method of preventing filament coiled fon a nandrel from slipping thereon comprising'passing the same through solution'ot sodium tetraborate; v 7. p The methodof preventing a metal filament coiled on .the' mandrel from 'slipping thereon, comprising'* passing the same through" a hot supersaturated solution' of -sodium tetr'aborate, whereby ;'an""adhesive film forms immediately upon cooling after the filament is withdrawn from the solution. 8'. The method of preventing the relative movement of a m'and'rel -a'n'd a coil wound b thereon which comprises depositinga mate-.

6 cu'tlinto sections of proper lengths, w ii'ch "sections may have theporti'ons 'of'the'mandrel therein removed in the usual' manner,"

dissolving out in hydro- V Thesections of coiled filament, after removal'ot" then be cleaned by -treatment in a caustic solution in the rial from soluti'on onsaid coil and mandrel. 9. The method of preventing slippage between a filament and a mandrel'onwhich it is coiledcomprising temporarily cement-j ing the filament to the mandrel by means of 'a' flexible film of an inorganicsoluble material; I I

[10. Themethod of "preventingfslippage between a-filament and a" mandrel on which it is coiled comprisinggannealing "the same and temporarily cementing the filament to the mandrel'by means of a fl'exible film of rated solution of an alkali borate, whereby a flexible cementing film forms immediately upon cooling when the filament is With. drawn from the solution.-

is minimized, and passing said fi1a-" "comprising applying a hot solution of ad- 7 hesive material thereto.

material temporarily fixed in place thereon: bymeans of a solution of an alkali borate applied thereto.

15. A mandrel wound with metallic filamentary material and coated with a hot supersaturated solution of an alkali borate whereby an adhesive film, temporarily afiixing the filamentary material in place on the mandrel, is immediately formed upon cooling.

16. A mandrel of iron wire or the like Wound with refractory metal wire temporarily held in place by a solution of sodium tetraborate applied thereto.

17 Refractory metal wire wound on a mandrel of iron Wire or the like and treated with a hot supersaturated solution of sodium I tetraborate to temporarily hold the wire in place on the mandrel.

18. An iron wire mandrel or the like to which a coil of tungsten wire is temporarily afiixed .and prevented from slipping thereon by means of a hot solution of sodium tetra-- borate, whereby the same may be cut into sections without relative displacement between the mandrel and the filament.

19. A metal mandrel wound with tung sten wire or the like, annealed and slippage between the wire andmandrel prevented by a film of an alkali borate applied thereto.

20. A readily soluble metal mandrel wound with tungsten wire or the like, annealed and coated with a hot supersaturated solution of an alkali borate, whereby slippage between the wire'and mandrel is pre' vented by the formation of a film of adhesive material.

In testimony whereof, I have hereunto subscribed my name this 17th day of August, 1923. I

EDWARD ROBERT SCHMID. 

